Molecular biology has revolutionized breast cancer treatment increasing survival rates dramatically. Nevertheless, for too many women, particularly those at high risk from germline genetic mutations, case fatality remains high and cancer prevention remains elusive. The Breast Cancer Registry of Families BCFR), and the Metropolitan New York Registry, one of the six sites of the BCFR, remains committed to the continuation and restructuring of our infrastructure so that interdisciplinary research scientists can advance these issues using this unique resource. Our New York Registry, one of three clinic-based sites for the BCFR, enriches this resource for the scientific community in many ways, including first and foremost by providing 1,312 families and 4,729 individuals (57 percent of the families from the clinic-based sites). Our recruitment strategy emphasizes participation by families: 95 percent of all participants have at least one other family member also participating in the NY Registry;82 percent of all families have two or more members. Second, we provide a large number of carriers (195 with BRCA1 mutations, 101 with BRCA2 mutations) with detailed family and epidemiologic data. These unique characteristics of our New York family-based study population allows us to contribute too many important study designs crucial for unraveling the links between genes and the environment for high-risk women. These study designs, all of which New York investigators are employing in their own research as well as collaborative research, include retrospective cohort design among carrier families, sister-pair analyses comparing affected and unaffected sisters, and family triads. Further, 74 percent of our 4,729 participants have already donated DNA specimens for genetic analyses. Our New York team, comprised of epidemiologists, environmental scientists, pathologists, geneticists, and oncologists has the expertise and experience to contribute significantly to the research themes of the B-CFR 1) identification of genetic factors related to breast cancer risk;2) investigation of environmental modifiers of breast cancer risk;3) translational and clinical studies, and 4) behavioral response to familial breast cancer. To do so, we aim to continue and improve the New York component of the B-CFR infrastructure by contributing to the following nine platforms: Follow-up, Expansion of Families, Clinical Research, Pathology, Biospecimen, Molecular, Analytic, Behavioral/Survivorship, and Administrative and Coordination.